How long does a bad foot sprain take to heal?

Could take : Upto couple of months really would depend on severity and how adherent you are to the treatment protocol.

Varies: Most foot sprains heal within days or weeks. Its important that you be evaluated by an orthopedist to rule out a midfoot sprain which can often be missed upon initial evalauation. Midfoot sprains can sometimes be a serious injury that may require surgical intervention.

Depends on : Type or grade od sprain. If mild approx 2 weeks, moderate sprain about 3-4 weeks severe or grade 3 6 weeks and sometimes needs surfical repair. See podiatrist for diagnosis and treatment options. Remember rest ice compression and elevation until looked at.